The Objective

A way of finding harmonious colour groups with minimum difficulty

Colour experts find harmonious colour groups all the time, but they're talented and experienced, and they often understand quite a lot about colour theory. They know that applying colour theory is the easy way to achieve prefessional-looking colour schemes. Most of the rest of us, however, prefer to avoid the drudgery of learning something that complicated. So we need help from an assistant already knowledgeable about colour theory.
     The assistant should be able to take into account a number of characteristics of the image in suggesting a colour scheme for it. For example, if a region is very large it should not be very strongly coloured, or the effect will be garish. On the other hand, if it is information-rich and important, it may need to be more strongly coloured, to draw the user's attention, and a certain amount of garishness may be tolerable.
     Different people will prefer different colour schemes, and an individual may tire of a particular colour scheme after a time. The assistant needs to devise colour schemes which can easily be personalised by the user according to her or his preference on a particular day, without compromising pragmatic requirements such as distinguishability of the image components.